Guys, if someone of you still cannot use G Pay, you can try my Automate flows. I wrote them and using for already a month and have no problems with payments.
Please add swipe to seek feature.
Fingerprint doesnt work in some apps, for example Privary.
For those, who cannot remove updates - try to disable device admin for G Pay and Device lost, then delete data of Play Services, then uninstall updates. Please note, that you will lose all your cards in G Pay.